Emergency Flasher Trick
Elder User
Joined: Aug 2008
Posts: 505
Likes: 0
Yeah
You can take a standard 20amp fuse and slip it right in the 3 & 4 slots while your trailer's hooked up. Lights up your stop and running lights. Not really functional, but looks cool at night around the campsite. Just remember that it'll cause your lights to burn out sooner (better carry some spare 1157's), unless you're running LED's.
You can take a standard 20amp fuse and slip it right in the 3 & 4 slots while your trailer's hooked up. Lights up your stop and running lights. Not really functional, but looks cool at night around the campsite. Just remember that it'll cause your lights to burn out sooner (better carry some spare 1157's), unless you're running LED's.
Senior User
Joined: Mar 2010
Posts: 237
Likes: 2
From: South Texas
OK, I'm a real dummy here. You say all you have to do is plug a prong flasher in slot #3 and #4 and the tail lights will start flashing? Does this flasher somehow get power from the battery when vehicle not connected? Great idea if that's all their is to it.
Post Fiend
Joined: Sep 2006
Posts: 14,325
Likes: 14
From: Island Southeast Alaska
Trailer has to have it's own battery
Lead Driver
Joined: Sep 2007
Posts: 8,180
Likes: 669
From: Scio, OR
The tail lights and marker lights, actually.
Pin 4 is the wire that normally sends power from the truck to the trailer to charge the trailer batteries, if your trailer has batteries that are charged by the truck. When the connector is disconnected, there will be power on pin 4, since it's basically just hooked into the trailer batteries.
Pin 3 is the marker and tail lights.
Put a flasher relay between the two and you've created your own emergency flasher circuit.
I haven't tried this, I don't have anything to try it on. But it seems like it should work.
Pin 4 is the wire that normally sends power from the truck to the trailer to charge the trailer batteries, if your trailer has batteries that are charged by the truck. When the connector is disconnected, there will be power on pin 4, since it's basically just hooked into the trailer batteries.
Pin 3 is the marker and tail lights.
Put a flasher relay between the two and you've created your own emergency flasher circuit.
I haven't tried this, I don't have anything to try it on. But it seems like it should work.
Senior User
Joined: Sep 2010
Posts: 306
Likes: 2
From: Southwest Desert, AZ
Also works as a locator when amongst numerous travel trailers and when parking in the north woods and somebody needs to locate you after dark, as in your hunting buddy that is always late and cell phone service is out.
FYI the best place to camp has no cell service. Then you're at the beginning of life
FYI the best place to camp has no cell service. Then you're at the beginning of life
I'm hitting easy street
Joined: Nov 2009
Posts: 6,395
Likes: 27
From: Central Oregon
Got my flasher in the tool box!!! (third drawer down)
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Fleet Mechanic
Joined: Jan 2007
Posts: 1,741
Likes: 3
Just as a quick note here, there are two types of 2-prong flashers; the cheaper one is a thermal flasher, and the more expensive one is electro-mechanical.
The thermal unit can sometimes be problematic if you're trying to flash more than 2-3 lights at a time; it will flash much faster (or sometimes slower) if you're trying to flash a lot of lights. It's designed to be used in a car that doesn't tow trailers. The variation in flash speed is what's supposed to clue the driver in that a turn signal bulb is burned out.
The electro-mechanical version will handle many more lights, and give you a much more consistent flash speed.
-blaine
The thermal unit can sometimes be problematic if you're trying to flash more than 2-3 lights at a time; it will flash much faster (or sometimes slower) if you're trying to flash a lot of lights. It's designed to be used in a car that doesn't tow trailers. The variation in flash speed is what's supposed to clue the driver in that a turn signal bulb is burned out.
The electro-mechanical version will handle many more lights, and give you a much more consistent flash speed.
-blaine
Postmaster
Joined: Jul 2015
Posts: 4,392
Likes: 22
From: very South Texas
I have had for 3 years.. a plug in switch into the 7 pin on the trailer. for all outside lights to be on.. so Wife can locate trailer after dark..
and now will add a 2 pin flasher...
if you like use a 3 pin wig/wag turn signal flasher from a late 70's Chevy. and have turn signal lights flash alternately
and now will add a 2 pin flasher...
if you like use a 3 pin wig/wag turn signal flasher from a late 70's Chevy. and have turn signal lights flash alternately
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